In little time the macedonian army of Alexandrus III Magnus exceeds the rivers Tigri and the Euphrates and enters before to Babylon and then to Persepoli.
Some centuries after try the same enterprise first the proconsul Marcus Licinius Crassus and after the triumvir Marcus Antonius but they fail the objective or the target.
Why? What had in less than Alexandrus ? Was perhaps Alexander more expert in tactics, in strategy or logistics of the roman duces?
These questions deserve answers and certainly will have answers.